Shaft construction



c. D. R. scHAEFl-'ER SHAFT CONSTRUCTION Aug. 30, 1927.

Filed Dec. 16. 1925 ,Patented Aug. 3o, 1.927.

UNITED STATES y CHABLESD. R. SCHAEFFEB, OF FORT DODGE, IOWA.

snarfr CONSTRUCTION.

The object of my invention is to provide a shaft construction, wherebyrotary motion transmitted by means of a shaft may be somewhat cushioned during the transmiss1on.

More' particularly, ,it is my object to provide a shaft construct-ion, which `can be inten. posed between moving parts insa motor vehicle orother plece of machinery, in such manner that varying'speeds of rotation 4of one 4shaft or part of a shaft may be cushioned in the transmission to another shaft or part of a shaft, whereby the tendency .of the shafts to break or twist off may be largely reduced.

Another urpose of my invention is to provide two s afts Orfshaft sections connected by discs and by aiplurality of spaced spring rods or the like.

Still a further 'purpose of my invention is `to provide in such a device means whereby :when a certain degree of twisting movement Vhas been given tjo the spring rods, the two shaft sections will be locked together, soas Ato revent` any .further twisting.

-ith these and other objects in view, my lnvention consists in the construction, ar-

rangement and combination ofthe various parts of myv shaft construction, whereby the objects contemplated are attained, as 'hereinafter more fully setforth, pointed out in my claim, and illustrated in the accompany- ,in drawings, in which:

igure 1 'shows aside elevation of a shaft construction embodying my invention, parts being broken away and parts being shownange in section.

Figure '2 is a detail, sectional view taken on the line 2-2 of Figure 1.

Figure 3 is a side elevation ofthe device, .parts being broken away and parts bei-n0 shown in section .for illustrating additiona features of the invention; and

Figure 4 is a'detail, sectional view taken on the line 4--4 of Figure 3. In the accompanying drawings, I have used the reference numerals 10 and 11-to indicate aligned shafts or shaft constructions.

. Let it be assumed for purposes of illustration thatit is desired to transmit rotary movement from the shaft 10 to the shaft 11 and to cushion such transmission in order to reduce the strain' on the shafts or shaft parts.

Each of the shafts or shaft sections 10 and 11 is provided at its end with an annular disc Application mea member is, 1925. serial Na. 75,1715.

is arranged between the vdiscs 12 on the shafts 10 and 1.1.

The shaft member 14 .is provided nearits ends with annular flanges or discs 15. The' portions 14% of the shaft member 14 projecting beyond the discs or lianges 15 are received in the recesses or sockets 13 and are journaled therein by means 16.

Each of the discs is provided in its peripheral face with a plurality of circumferentially spaced grooves 17, which extend parallel with the axes of the shaft and parallel -to the axis of the shaft on which the disc 12 is formed. l-

These grooves' extend from that face of the disc 12 adjacent to the flange 15 for a substantial distance and terminate in .inwardly deepened recesses 18.

A plurality of spring' steel rods 19 are arranged between the discs 12 of the respective shafts and have por-tions 19Il received in the grooves 17 and portions 19h in-turned -and received in the deepened recesses 18.

The diametersof the flanges 15 Iare such thattheir peripheral faces stand within the circle of the steel rods 19, as shown for instance in Figures 1 and 2.

. In order to hold the rods 19 in place in the grooves 17 a cover sleeve 2Q is screwed onto each disc 12 ,in such manner as to overlap the lortions-19a of the rods 19, and also to over ie the peripheries of the discs or Set screws 21 may be employed for holding the cover sleeves 20 against accidental displacement.

The length of the shaft 14 is such with relation to the length of the spring steel l rods 19 that when the rods 19 are straight and parallel with the axis ofthe shaft member 14, the ends of the shaft member 14 may be slightly lspaced from the bottoms of the sockets or recesses 13, and the faces of the anges 15 may be slightly spaced from the adjacent faces of the discs 12, as clearly indicated at the left-hand end jof Figure 1.

When rotation is impartedto the shaft member 10, it is obvious that its disc 12 will be rotated for carrying with it the rods 19, and thereby imparting rotation to the shaft 11 through its disc 12.

Insomuch as the rods 19 are of spring maof roller bearings terial, such imparting of rotation lwill tend to twist the rods 19 out of lines parallel with the extended axes of the shafts 10 and 11, and will tend to pressthe rods 19 into spiral lines.

The transmission of motion from the shaft 10 to the shaft 11 will thereby be somewhat cushioned.

The importance of such cushioning will, of course, be obvious. c

If such a device wereemployed in ordinary automobiles, the strains on the differential and other gears and shafts would be reduced, to a ver great extent.

When the sha t member 14 is employed, it will be seen that when the twisting movement is given to the rods 19, the distance between the shafts 10 and 11 will be slightly shortened, whereupon the ends of the shaft portions 14:'CL will bind against the bottoms of the recesses 13 and the discs or-flanges 15 will 'bind against the discs 12 and prevent any further relative rotation of the shaft member 10 with the shaft member 11, and any further twisting l'of the rods 19.

This structure and operation are suchras to permit the cushioning and reduction of strains in the transmission of power, while at the same time affording a very strong and studdy device not likely to be broken or torn to pieces by any strains, which would otherwise injure the mechanism, with which my device is employed.

A device of this kind will reduce the strain upon all the mechanisms to which power` is` applied,and is of special value to motor vehicles, where there 1s a great variation in speed and frequent changes in the speed of rotation transmitted from one shaft to4 another. l

Such'a structure as this reduces the strains upon all the parts including gears, shafting,

wheels, and 'reduces the vibration on the In a device oftheclass described, a pair of shafts arranged in alignment and spaced from each other, said shafts having at their adjacent ends annular discs, a plurality of spring steel rods havingtheir ends mounted non-slidably in said discs, collars-mounted on s aid discs for holding said-rods in place, said discs having aligned sockets,- a shaft section having its ends arranged in said sockets and having flanges adjacent to said discs, said shaft section being of such length as to permit limited rotary movement of said first shafts with relation to each other, whereby said rods are twisted for slightly shortening the distance between the first shafts, and being of such length as to" then l bind at its ends and prevent further relative rotary movement of the first shafts.

Des Moines, Iowa, December 3,1925.

CHARLES D. n.'scnlinrrnnjl 

